mid-15c., a term in logic, from Middle French predicat and directly from Medieval Latin predicatum, from Latin praedicatum "that which is said of the subject," noun use of neuter past participle of praedicare "assert, proclaim, declare publicly," from prae- "forth, before" (see pre-) + dicare "proclaim" (see diction). Grammatical sense is from 1630s. Related: Predicative; predicator; predicatory.